Journal of Applied and Natural Science
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Evapotranspiration mapping for agricultural water management: An overview
Get PDFEvapotranspiration (ET) is an essential component of the water balance. Any attempt to improve water use efficiency must be based on reliable estimates of ET, which includes water evaporation from land and water surfaces and transpiration by vegetation. ET varies regionally and seasonally according to weather and wind conditions. Remote sensing based agro-meteorological models are presently most suited for estimating crop water use at both field and regional scales. Numerous ET algorithms have been developed to make use of remote sensing data acquired by sensors on airborne and satellite platforms. The use of remote sensing to estimate ET is presently being developed along two approaches: (a) land surface energy balance (EB) method and (b) Reflectance based crop coefficient and reference ET approach. The reported estimation accuracy varied from 67 to 97% for daily ET and above 94% for seasonal ET indicating that they have the potential to estimate regional ET accurately. Automated contours are not confined to specific pre-determined geographic areas (as in MLRA), require less time and cost. The spatial and temporal remote sensing data from the existing set of earth observing satellite platforms are not sufficient enough to be used in the estimation of spatially distributed ET for on-farm irrigation management purposes, especially at a field scale level (~10 to 200 ha). However, research opportunities exist to improve the spatial and temporal resolution of ET by developing algorithms to increase the spatial resolution of reflectance and surface temperature data derived from K1VHRR/Landsat/ASTER/MODIS images using same/other-sensor high resolution multi-spectral images
Plant phenological response to microclimatic variations in an alpine zone of Garhwal Himalaya
Get PDFThe impact of microclimatic variations on the developmental stages of common alpine plant species at four primary phenology sites at Dayara meadow of Garhwal Himalayas (Uttarakhand) was studied. The study revealed that the variations in the topographical features and environmental conditions directly influenced the phenology of the alpine plant species. Site I and IV showed great variation in the timing of phenological phases whereas, site III and IV showed approximately similar phenological timings. Anemone obtusiloba and Anaphalis contorta showed early flowering whereas Aconitum heterophyllum, Bupleurum longicaule and Parnassia nubicola flowered in late August and early September. P. nubicola had a shorter flowering period whereas Tanacetum longifolium.and A. nepalensis had the longest flowering period. Taraxacum officinale and Geum elatum flowered twice in the season
Immune response and status of epizootic ulcerative syndrome (EUS) affected fishes Channa punctatus and Clarias magur
No full textIn Epizootic ulcerative syndrome (EUS) affected Channa punctatus and Clarias magur, the serum total proteins were decreased by 24.63% and 38.75% respectively along with A:G ratio. During immune response, the antibodies produced were found to be positively exponential with the amount of antigens (bacteria, fungus and viruses). The present changes may be because of the changing environmental conditions especially temperature fluctuations producing stress conditions in the fishes
Isolation and characterization of Fusarium oxysporum, a wilt causing fungus, for its pathogenic and non-pathogenic nature in tomato (Solanum lycopersicum)
Get PDFCollection of soil and plant samples from nine different geographical locations in Uttar Pradesh state of India was made. Composite soil was analyzed for its nutrient status. A total of sixty isolates of Fusarium species were recovered from the soil and plant samples. Among these, thirty nine isolates were identified as Fusarium oxysporum on the basis of their morphological and molecular identification. The pathogenicity test was conducted on tomato variety Pant T-3, disease incidence ranged from zero to 78.74%. Among F. oxysporum isolates, five were non pathogenic and three were found strongly pathogenic.Non-pathogenic isolates were tested for their antagonistic effect against most pathogenic isolates of F. oxysporum. The results showed that the Isolate no. 40 showed the highest antagonistic activity in inhibiting radial growth of pathogenic isolates
Morphological and cultural characterization of Alternaria alternata (Fr.) Keissler blight of gerbera (Gerbera jamesonii H. Bolus ex J.D. Hook)
Get PDFFungal blights are among the major concern for limiting the cultivation and production of many ornamental and flowering plants. Gerbera is an important cut flower with great export potential. However, it is infected by many pathogens in the protected cultivation. The severe infection of fungal blight caused by Alternaria alternata (Fr.) Keissler was observed in the polyhouse condition. Hence, in this study, critical morphological and cultural studies were done to understand the pathogen behaviour. The fungus A. alternata produced profuse mycelium on Potato Dextrose Agar (PDA) with an average width of 4.42 ?m in diameter, conidiophores, conidia and intercalary chlamydospores measured as 42.26 x 4.29 ?m, 47.16 x 13.49 ?m and 7.22 ?m in diameter, respectively. The synthetic media viz., Leonions’s agar, Glucose-peptone agar and Sabourand’s agar and non-synthetic media, Oat meal agar and PDA were excellent for the mycelial growth and conidial production of A. alternata
Correlation of water’s physico-chemical characteristics and trematode parasites of Channa punctata (Bloch) in Awangsoi lake, Manipur, India
Get PDFInfection with trematode parasites can lead to severe change in nutrient content and may result in host mortalities and character of a water body may influence the parasitic fauna. Hence a study was carried out from 2010 to 2011 to find out a correlation of water’s physic-chemical characteristics and trematode parasites of Channa punctata (Bloch) in Awangsoi Lake, Manipur, India. During the present investigation three species of trematodes were recorded. In the present study there were concurrent infections by two or more parasite species. The percentage of infection was positively correlated with temperature, pH, DO and conductivity in Awangsoi Lake. There was a significant positive correlation (r = 0.652; p<0.05) with FCO2 and a negative correlation with alkalinity. Seasonal variation in the occurrence of these parasites may be attributed to ecological conditions, particularly distribution of intermediate hosts and also the age of the host and the life cycle of the parasite species
Yield of aerobic rice affected by high temperature stress during summer season -A study from red and laterite zone of West Bengal, India
Get PDFField experiment on the performance of aerobic direct seeded rice (ADSR) under red and laterite zone of West Bengal was conducted at Rice Research Station, Bankura, West Bengal, India during summer season, 2012. The experimental soil was sandy loam with acidic in nature (pH: 5.2). The results exhibited that the grain yield (1 t ha-1) of rice in aerobic situation was low. This might be due to high atmospheric temperature during flowering period, which results in poor grain setting in panicle and most of them became chaffy due to spikelet sterility. Ultimately, it produced low grain yield of rice in aerobic situation during summer season due to high temperature at flowering period, grain formation and grain ripening stages. Thus, aerobic rice system of cultivation needed good management practices
Phylogenetic analysis among Indian squill Urginea indica Kunth. Liliaceae
Get PDFIn the present study on Urginea indica, twelve different populations from southern part of India is considered. Fifteen parameters have been scored for each population to understand the relationship between different races. The main objective is to trace phylogeny in populations of U. indica to construct phylogenetic tree. The phylogenetic tree obtained is an unrooted tree. The parsimony tree describes that Shimoga and Chamundi hill populations have parallely evolved and forms the out group. Dopaegowdanapura population has given rise to Gopalaswamy betta, Gopalaswamy betta has given rise to Banganavadi and Banganavadi has given rise to one population which is missing in the tree and the missing population has given rise to Gorur on one hand and to Krishna Raja Sagar island and Gandhi Krishi Vighnayana Kendra on the other hand. Krishna Raja Sagar island and Gandhi Krishi Vighnayana Kendra shares a common clade. Gorur has given rise to Papanasini and Papanasini has given rise to Channamallipura, from Channamallipura another population has been evolved which is missing and the missing population has given rise to Basavanahalli and Ranganthittu which shares a Common clade. The Parsimony tree shows that these populations have evolved parallel. Dopaegowdanapura is the oldest from which all others are evolved. Ranganathittu and Basavanahalli form the youngest and latest. Therefore it is an unrooted tree with distance. Each population varied in their morphology and chromosome number and called as cytotypes. Difference in morphological character is mainly because of genetic characters. Habitat does not seem to play major role to mould morphological features
Water quality assessment of river Tons, Dehradun (Uttarakhand), India
Get PDFWater quality of Tons river near Tapkeshwar temple in Dehradun was assessed in terms of their physicochemical parameters. Samples were collected on the monthly basis since January to March, 2011 from three sites viz confluence zone of temple, upstream and downstream river water. Total number of nine samples were analysed and a correlation matrices among parameters was determined. River water was showing alkaline character throughout the study period. pH, alkalinity and chloride were found to be under the acceptable limit of BIS (2009),although turbidity and hardness were exceeding the limits at all three sites but total dissolved solid only on confluence zone and downstream river sites. Water samples from the confluence zone near the temple showed slightly higher concentration of all the parameters than other sites. The present study reveals the slight effects of various religious activities on confluence site of tons river water near the temple which were found to be under the prescribed permissible limits of BIS (2009)
Phytochemical screening and antibacterial effect of root extract of Boerhaavia diffusa L. (Family Nyctaginaceae)
Get PDFBoerhaavia diffusa belonging to the family of the Nyctaginaceae is mainly a diffused perennial herbaceous creeping weed of India. The present study deals with the investigation of phytochemical analysis and evaluation of the antimicrobial activity of the aqueous and methanolic extract of the roots of Boerhaavia diffusa. The result revealed the presence of alkaloid, glycoside, saponins, flavonoids, polysaccharides, steroid and tannin in both the root extracts. B. diffusa root extract possesses antimicrobial activity as the zone of inhibition was observed for both gram positive as well as gram negative bacterial strains